﻿// See https://aka.ms/new-console-template for more information
Console.WriteLine("Hello, World!");

a GetA = new b();
GetA.value = "123123";
var res=GetA.getvalue();




public interface a 
{
    public  string getvalue();
    public string value { get; set; }
}


public abstract class absA : a
{
   // public virtual string getvalue() =>"我是默认值";
    public string value { get; set; }

    public abstract string getvalue();
}

public class b: absA
{

    public override string getvalue ()
    {
        var res = value;
        return res;
    }


}